Punching　shear　failure　of　slab-column　joints　tends　to　trigger　the　progressive　collapse　of　a　flat　plate　structural　system.　A　static　progressive　collapse　test　was　conducted　on　a　2×2　bay　flat　plate　substructure　with　a　missing　interior　column.　At　first,　a　downward　concentrated　force　was　applied　on　the　central　removed　column　till　the　initial　punching　shear　failure　occurred.　Subsequently,　a　downward　uniformly　distributed　load　was　alternatively　imposed　on　the　slab,　and　the　load　was　maintained　until　the　progressive　collapse　of　the　substructure.　The　collapse　mechanism　and　collapse-resisting　resistance　of　the　substructure　under　different　deformation　stages　were　analyzed　and　evaluated.　Results　show　that　the　punching　shear　failure　of　the　slab-column　joint　within　a　substructure　exhibits　a　certain　level　of　ductility.　But　the　tensile　force　of　the　membrane　action　developed　in　the　slab　results　in　a　50%　decrease　of　the　punching　capacity　of　the　joint　compared　to　that　calculated　by　the　Chinese　code.　In　the　initial　stage,　82%　and　18%　of　the　applied　load　are　resisted　by　the　middle　edge　and　corner　columns,　respectively.　Then　the　slab-column　joints　at　the　middle　edge　columns　are　gradually　damaged　as　the　deformation　increased,　which　lead　to　a　decrease　and　an　increase　of　the　loads　carried　by　the　middle　edge　and　corner　columns,　respectively.　At　the　end　of　the　test,　51%　and　49%　of　the　applied　load　are　resisted　by　the　middle　edge　and　corner　columns　when　the　substructure　collapsed.　At　small　deformation,　the　substructure　resists　the　load　via　out-of-plane　bending　capacity　and　in-plane　compressive　membrane　action.　The　compressive　membrane　action　contributes　to　12%　of　the　collapse　resistance　when　the　joint　of　the　central　column　damaged　in　punching　shear.　At　large　deformation,　both　the　residual　flexural　capacity　of　the　remaining　joints　and　the　tensile　membrane　action　contribute　to　the　collapse　resistance.　When　the　slab-column　joints　are　severely　damaged,　only　the　integrity　reinforcement　at　the　bottom　of　the　slab　effectively　provides　the　collapse　resistance　in　the　form　of　tensile　membrane　action.　©　2018,　Editorial　Office　of　Journal　of　Building　Structures.　All　right　reserved.